Watery diarrhea associated with pancreatic islet cell carcinoma.

A patient with severe watery diarrhea and a non-beta islet cell carcinoma of the pancreas producing five hormones (secretin, serotonin, enteroglucagon, vasoactive intestinal polypeptide, and pancreatic glucagon) is described. We have demonstrated massive pancreatic hypersecretion to be a major factor in this patient's diarrhea. Possible inter-relationships of the actions of five hormones present in excess in the patient are discussed.     

Effects of SMS 201-995, a somatostatin analogue, on the exocrine pancreatic secretion and gut hormone release in dogs

The effect of SMS 201-995, an analogue of somatostatin, on pancreatic exocrine secretion was investigated in both interdigestive and digestive states in dogs. In four dogs with gastric and Thomas duodenal cannulas, the pancreatic juice was collected by direct cannulation of the main pancreatic duct. SMS 201-995 was infused intravenously at doses of 0, 15, 30, 60, and 120 ng/kg/hr for 2 to 3 hours in the following experimental conditions: (1) interdigestive pancreatic secretion, (2) pancreatic secretion stimulated by the intravenous infusion of both secretin, 0.06 CU/kg/hr, and cholecystokinin octapeptide (CCK8), 0.03 microgram/kg/hr, and (3) pancreatic secretion after ingestion of a test meal. Pancreatic juice was analyzed for volume and outputs of bicarbonate and protein. Plasma levels of motilin, pancreatic polypeptide (PP), CCK, and secretin were determined by radioimmunoassay. SMS 201-995 inhibited significantly the pancreatic secretion and release of hormones, including secretin, CCK, PP, and motilin, in all three experimental conditions. The inhibitory action of SMS 201-995 on pancreatic secretion and hormone releases was dose dependent.     

The effects of sulfasalazine on human male fertility potential and seminal prostaglandins

Fertility parameters of 10 men with chronic inflammatory bowel disease under treatment with sulfasalazine for at least 5 years were compared to those of 19 control subjects. Seminal parameters examined included ejaculate volume, sperm number and concentration, sperm motility index, sperm viability, pH, zinc concentration, prostaglandins E and F2-alpha, prolactin and 7 classes of sperm morphology. In addition, plasma concentrations of follicle-stimulating hormone, luteinizing hormone, testosterone and prolactin were noted. The data indicate that sulfasalazine therapy reduces semen quality and that this effect can be reversed upon removal from therapy. This reversal is independent of seminal prostaglandin concentrations.     

CCK-receptor antagonists proglumide and loxiglumide stimulate bile flow and biliary glutathione excretion

The mechanism for the choleresis induced by CCK-receptor antagonists, proglumide, loxiglumide, and CR 1409, was examined in anesthetized rats and compared to the effects of CCK itself. These agents were infused intravenously over a 2-hr period, and bile flow, and biliary excretion of bicarbonate, total bile acids, and glutathione were measured in 30-min intervals. All three antagonists produced a dose-dependent choleresis, but a significant decrease in bile acid excretion, indicating that they stimulate bile flow via a bile acid-independent mechanism. The increase in bile flow was associated with a parallel increase in biliary glutathione and biocarbonate output in rats treated with proglumide and loxiglumide. In animals pretreated with acivicin to inhibit gamma-glutamyltransferase activity, proglumide was shown to stimulate biliary excretion of reduced glutathione (GSH), but not glutathione disulfide (GSSG), indicating the absence of oxidative stress in the liver. GSH output was increased by only 0.5–0.9 µmol/30 min after infusion of proglumide at a dose of 75 mg/kg/hr, whereas bile volume was increased 0.2–0.4 ml/30 min, indicating that this increased biliary GSH excretion can account for only a small fraction of the increased bile volume, given an osmotic efficiency for GSH of 34 µl/µmol. In contrast to CCK receptor antagonists, CCK itself had no effect on bile flow and outputs of bicarbonate, GSH, and bile acids, suggesting that the effects of the antagonists are not related to their interaction with CCK receptors. These findings demonstrate that proglumide and loxiglumide stimulate a bile acid-independent bile flow that is only partially explained by an increase in GSH excretion.     

Plasma secretin concentrations in fasting and postprandial state in man.

Plasma immunoreactive secretin concentrations were determined in both healthy subjects and patients with duodenal ulcer. The modified radioimmunoassay method could detect significant increases in the plasma secretin concentrations when 0.05 N HCl was infused intraduodenally at a rate of 1.1 and 2.2 ml/min. The mean fasting plasma secretin concentration of 13 normal healthy subjects was 4.4 +/- 0.38 pg/ml which was significantly less (P less than 0.01) than that of 13 duodenal ulcer patients, 6.9 +/- 0.64 pg/ml. In both groups ingestion of a meat-containing meal resulted in significant increase in the plasma secretin concentrations. Recording of pH from proximal duodenum indicated that pH fell periodically below 4.5 during the postprandial period, indicating that only a short segment of proximal duodenum was exposed to acid after meal. The postprandial rise in plasma secretin levels was abolished when antral pH was raised 5.5 by intragastric infusion of 0.3 N NaHCO3 solution. These observations indicate that although fasting plasma secretin levels are low, the plasma secretin levels increase significantly after ingestion of a meal. This increase appears to be attributable to an increased amount of acid delivered to the proximal duodenum, and patients with duodenal ulcer were found to release more secretin during the postprandial period than normal subjects.